Strap connector



Dec. 26, 1.961 M. o. DERRICKSON ET AL STRAP CONNECTOR Filed May 8, 1961 S ts The present invention relates to the art of strapping bales, boxes, bundles and the like and more particularly to an improved connector or buckle for securing the ends 1 of a flexible strap which is looped tightly about a bale, box, bundle or the like.

The strapping art may be divided roughly into two categories: strapping compressible bundles or bales while they are held under compression in a press and strapping relatively incompressible boxes, packages and the like. The techniques of strapping in the two categories are generally somewhat difierent. For example, not always but usually, when strapping a bale which is held under compression in a press, the strap is pre-cut to length before being placed in position about the bale and when the ends of the strap are suitably secured together the pressure of the press is released, whereupon the strap is subjected to tension and prevents the bale from returning to its uncompressed dimensions. In this instance, the strap is not tensioned prior to securing the ends together, or at most is tensioned only slightly. When the object being strapped is not held in a press, it is customary or normal to withdraw an end of the strap from a large roll and tighten it about the object with the aid of a tensioning or stretching tool before securing the over lapping portions of the strap together and cuting the length of strap being used from that portion remaining on the roll. in this latter instance it is the usual practice to secure the strap in position by means of a metal sleeve which is crimped about the overlapping portions thereof, whereas in the baling press operation the strap ends are normally held by some form of buckle.

In addition to the two above mentioned categories of procedure, there are also two general types of strapping material. For many years the most common has been in the form of a flat steel band made in a variety of widths and thicknesses. These bands or straps are relatively stifi so that when folded over to engage a portion of a buckle they do not readily pull loose. When the steel straps are used on relatively incompressible packages, a sleeve is positioned over overlapping ends of the strap and the edges of the sleeve and of the strap itself are nicked to provide interlocking portions which hold the strap ends together. More recently, various forms of non-metallic strapping have come into popularity and it is with these that the present invention finds its greatest utility. While non-metallic strapping may be made in diiferent ways and of different materials, one of which may be mentioned by way of example only is in the form of a hat band consisting of a plurality of rayon tire cords secured sideby-side by a suitable adhesive. While the non-metallic flexible strapping offers many obvious advantages, it cannot be held under tension by the same devices usedwith steel strapping. For example, because of its greater flexibility, the non-metallic strap will not hold when merely bent or folded about a bale buckle. When a seal or sleeve is employed with non-metallic strapping, interlocking deformations at the edges of the strap cannot be relied upon to hold it but instead the seal must be crimped across the entire Width of the strap. Without going into the various problems involved in providing a suitable seal for the overlapping ends of a flexible, nonmetallic strap, sufiice it to say that it has proven difficult to make an inexpensive seal which will hold the strap firmly when the strap is under substantial tension.

?atented Dec. 26, 1961 With the above background in mind, it is an object of the present invention to provide an improved connector for a flexible, non-metallic strap which will securely hold the strap under tension.

Another object of this invention is to provide a connector which will not damage a flexible, non-metallic strap and will permit the strap to be tensioned to substantially the full strength of the strap itself.

A further object of the invention is to provide a strap connector which may be laced readily without pro-cutting the strap to length. I

A still further object of the invention is to provide a strap connector which will permit the strap to be tightened after being associated or laced with the connector.

Another object of the invention is to provide an improved strap connector of simple, one piece construction.

A still further object of the invention is to provide a connector for flexible, non-metallic strapping which will lie flat on the package.

Other objects, features and advantages of the invention will become apparent as the description of a preferred embodiment thereof proceeds.

Referring now to the drawing:

FIG. 1 is a plan view of the connector;

FIG. 2 is a side elevational view showing a strap in the process of being laced with the connector;

FIG. 3 is a side elevational view showing a strap laced with the connector and under tension; and

FIG. 4 is a perspective view showing one manner of tightening a strap about a package when using the connector of the present invention.

The strap connector of the present invention is formed of a single piece of preferably round wire. As seen in FIG. 1, the connector is generally rectangular and has a first pair of strap engaging arms 10 and 11 on one side thereof and a second pair of strap engaging arms 12 and 13 on the opposite side thereof. The arms of each pair of arms are straight, parallel to one another and, as seen in FIG. 2, spaced apart sufficiently to permit a strap 14 to be positioned therebetween. Arms 10 and 12 constitute terminal portions of the wire and their respective cooperating arms 11 and 13 constitute or are formed of intermediate segments of the wire. -For convenience of reference, arms 10 and 12 will be referred to throughout as the first arms of their respective pairs and arms 11 and 13 will be referred to as the second arms.

A straight run 15 of the wire connects arm 10 to arm 13 and extends perpendicular to both. Arms 10 and 13 are thus parallel to one another but, as may be seen in FIGS. 2 and 3, are located in different horizontal planes. A straight run or sector 16 of the wire connects arms 11 and 13 and extends perpendicular to both and, as shown in FIGS." 2 and 3, these two arms are located in the same horizontal plane. A bent segment of the wire interconnects arms Hand 12. This latter segment has a first portion 17 which underlies and extends parallel to the straightrun 15 and a second portion 18 extending outwardly and upwardly at an angle to the-first portion 17. This outward and upward slope of the wire positions arm 12 above run 15 and sector 16 and locates said arm in a common plane with arm 10, said plane being parallel to a plane through the sector or run 16 and arms 11 and 13. The two ends of the wire, that is, the free ends of arms 10 and 12, lap or overlie the sector 16 but are spaced above sector 16 so that in lacing the connector a loop of the strap may he slipped over the free end of either arm, as will now be described.

Aspreviously mentioned, some strapping procedures involve the use of a strap which is pie-cut to length so that it has two free ends and others involve the use of a strap which has only one free extendingfrom a large roll of strapping material. The present connector is adapted to facilitate either of these procedures. The lacing operation may be best understood by referring to FIG;

2. The free end 19 of strap 14 is drawn from the supply roll 2% and beneath and around the package indicated at 21. End 19 is then fed upwardly through the central opening of the connector and down and around arm 12 between arms 12 and 13 and thence outward between arm 13 and an intermediate portion of the strap. The free end of the strap is now engaged with the connector. If the strap has two free ends, the other end may be laced with arms and 11 in the same manner. However, when the strap is connected to a roll as shown, it may be very readily connected to arms 10 and 11 in the following manner. A loop 22 is formed in the strap and pushed up through the central opening of the connector. The loop is then bent over as shown in FIG. 2 and the closed end thereof moved endwise of arm 10 and fitted over the free end of said arm. This leaves an excess amount of strap in the vicinity of the connector but by pulling on that portion of the strap between the connector and roll 20, the excess is withdrawn and the strap drawn tightly about arm 1% as shown in FIGS. 3 and 4. The strap may then be cut from the roll at a point a short distance from the connector.

The strap may be tensioned by hand as shown in FIG. 4 or by a suitable tensioning tool. Either of the upper ends of the strap may be pulled to tighten it but the portion of the strap which is looped about the package cannot expand. This may be explained by referring to the right hand portion of FIG. 3 wherein an end (which may be that portion of the strap extending to roll is indicated as 21 and the portion of the strap extending around the package is indicated as 22. When portion 21 is pulled to the right, portion 22 slides relatively freely beneath it toward the left but when portion 22 attempts to move toward the right, portion 21 is pinched between it and arm 11 of the connector and will not move.

Tension on the strap produces a downward component of force on arms 10 and 12 and this in turn results in a torsional force on that portion of the wire of the connector forming arms 11 and 13. Arms 11 and 13 therefore twist slightly and permit arms 10 and 12 to move down from the normal position shown in FIG. 2 to the position shown in FIG. 3. Arm 10 cannot move downward any farther than shown in FIG. 3 because the free end thereof is now in contact with sector 16 of the connector and run 15 connected to the other end of said arm is resting upon and supported by the portion 17 of the connector. Arm 12 cannot move downward beyond the FIG. 3 position because its free end is resting on sector 16 and another portion of said arm, which crosses over run 15 as shown in FIG. 1, is resting on run 15. It is important to the present invention that arms 10 and 12 remain substantially parallel to their respective associated arms 11 and 13 when the strap is under tension and also it should be noted that the strap is not pinched between arms 10 and 11 or between arms 12 and 13, even when the strap is under full tension. Any pinching of the strap between arms 10 and 11 or 12 and 13, particularly an uneven pinching, will result in damaging the strap and is apt to cause the strap to break at the place where it is pinched.

Preferably, the distance between the run 15 of the wire and sector 16 is just slightly greater than the width of the strap with which the connector is to be used whereby the pull of the strap is distributed uniformly over the length of the two pairs of arms. Also, preferably, the wire of which the connector is formed should be of sufiicient diameter as to avoid sharp bends in the strap where it passes around the connector. arms. For maximum strength it is desirable to keep the angle between portion 18 of the wire and the extended center line of portion 17 below thirty degrees. Tension on thestrap of course tends to straighten that run of the wire having the portions 17 and 18 and when the angle between them is greater than about thirty degrees this run is apt to straighten somewhat with the result that the upper end of arm 12, as viewed in FIG. 1, moves too close to arm 13 and pinches one side of the strap. When the connector is used with a narrow strap, it may be necessary to space the pairs of arms 10, 11 and 12, 13 proportionately farther apart than shown in the drawing in order to eliminate the necessity of a sharp bend between wire portions 17 and 18. The bend between portions 17 and 18 must be far enough away from arm 11 that portion 17 will provide a solid landing for the run 15 when the connector is drawn down as shown in FIG. 3.

While some variations in the construction of the connector are contemplated without departing from the spirit of the invention, it is essential that the strap engaging arms be parallel and that the arms of each pair remain sufliciently far apart under load to avoid pinching the strap therebetween. Also an essential feature is the provision of means whereby the arms of each pair cannot move into a common plane parallel to that portion of the strap extending about the package. For example, the plane between the longitudinal center lines of arms 1i) and 11 must always beat an angle to the plane of the strap as shown in FIG. 3.

Having thus described a preferred embodiment of the invention, what is claimed is:

1. A strap connector formed of a single piece of round wire, said connector being generally rectangular and having a pair of strap engaging arms on two opposite s des thereof, the arms of each pair of arms being straight and spaced apart sufiiciently to permit the strap with which the connector is to be used to be positioned therebetween, a first arm of each of said pairs of arms constituting a terminal portion of the wire and having a free end, the second arm of each pair constituting an intermediate segment of the wire, a separate run of the wire connecting the first arm of each pair to the second arm of the opposite pair, at least a portion of said separate runs of the wire lying in a common plane, a run of the wire connecting the second arms of each pair to one another, and the free ends of said first arms lapping said last mentioned run of the wire.

2. A strap connector formed of a single piece of round wire, said connector being generally rectangular and having a first pair of strap engaging arms on one side thereof and a second pair of strap engaging arms on the opposite side thereof, the arms of each pair being straight and spaced apart sufliciently to permit the strap with which the connector is to be used to be positioned therebetween, a first arm of each of said pairs of arms con= stituting a terminal portion of the wire and having a free end, the second arm of each pair constituting an intermediate segment of the wire, a straight run of the wire connecting the first arm of the first pair of arms to the second arm of the second pair of arms, a segment of the wire connecting the first arm of the second pair of arms to the second arm of the first pair of arms, said segment of the wire having a first portion underlying and parallel to said straight run of the wire and a second portion extending at an angle to the first portion, a straight sector of the wire connecting the second arms of each pair of arms to one another, and the free ends of said first arms overlying said straight sector of the wire.

3. A strap connector formed of a single piece of round wire, said connector being generally rectangular and having a first pair of strap engaging arms on one side thereof and a second pair of strap engaging arms on the opposite side thereof, the arms of each pair being straight and spaced apart sufliciently to permit the strap with which the connector is to be used to be positioned therebetween, a first arm of each of said pairs of arms constituting a terminal portion of the wire and having a free end, the second arm of each pair constituting an intermediate segment of the wire, a straight run of the wire connecting the first arm of the first pair of arms to the second arm of the second pair of arms, said straight run of the wire being perpendicular to the two arms which it connects, a segment of the Wire connecting the first arm of the second pair of arms to the second arm of the first pair of arms, said segment of the wire having a first portion underlying and parallel to said straight run of the wire and a second portion extending at an angle to the first portion, a straight sector of the wire connecting the second arms of each pair of arms to one another, said straight sector being perpendicular to both said second arms, and the free ends of said first arms overlying said straight sector of the wire.

4. A strap connector formed of a single piece of round wire, said connector being generally rectangular and having a first pair of strap engaging arms on one side thereof and a second pair of strap engaging arms on the opposite side thereof, the arms of each pair being straight and spaced apart sufficiently to permit the strap with which the connector is to be used to be positioned therebetween, a first arm of each of said pairs of arms constituting a terminal portion of the Wire and having a free end, the second arm of each pair constituting an intermediate segment of the wire, a straight run of the wire connecting the first arm of the first pair of arms to the second arm of the second pair of arms, a segment of the wire connecting the first arm of the second pair of arms to the second arm of the first pair of arms, said segment of the Wire having a first portion underlying and parallel to said straight run of the wire and a second portion extending at an angle to the first portion, a straight sector of the wire connecting the second arms of each pair of arms to one another, the free ends of said first arms overlying said straight sector of the wire, and said first arm of said second pair of arms crossing over the straight run of the Wire which connects the first arm of the first pair of arms to the second arm of the second pair of arms.

References Cited in the file of this patent UNITED STATES PATENTS Re. 5,333 Brodie Mar. 25, 1873 733,950 Eddleman July 21, 1903 2,552,957 Gore May 15, 1951 20 2,889,599 Perry June 9, 1959 FOREIGN PATENTS 10,880 Switzerland July 19, 1895 

